Properties of Solids
Elementary School
Definition
A solid has a fixed shape and a fixed volume because its particles are packed tightly together in fixed positions and can only vibrate. This explains why solids keep their shape and do not flow, unlike liquids and gases.
Worked examples
An ice cube sits on a table and keeps its cube shape even when tilted or moved.
The particles in the ice are locked in fixed positions, so the solid holds its shape.
A wooden block has the same volume whether you place it in a jar or leave it on a shelf.
Unlike gases or liquids, solids maintain a fixed volume because particles cannot move apart.
Common mistakes
- Solids can flow if you push them hard enough. → Solids cannot flow; their particles are locked in place and only vibrate. Flow is a property of liquids and gases, not solids.
- A solid takes the shape of its container like a liquid does. → A solid keeps its own fixed shape regardless of container. Fixed particle positions mean solids retain their shape independently.
- Particles in solids do not move at all. → Particles in solids vibrate in place but cannot move from their positions. All particles have thermal energy, so they vibrate even when locked in a solid.
Where you'll use it next
You'll apply solid properties when studying phase changes and particle diagrams, comparing states of matter, and understanding why materials behave differently under heat, pressure, or force in chemistry and physics.
See also
Reviewed by Pat Cheng, M.Ed. — StudyPug Curriculum Lead · Last updated June 6, 2026